I came back to edit this up a bit. was too wordy and initial impressions needed to settle.
 
Boy looks like there's some competition over there in the Just Listened to Some Fostex T-50rp's Today thread! Nothing beats the original here though, often imitated, as they say.
Anyhow Armaegis helped me think straight again! What a guy.
Pursuant to his P.M. response again( sounds pretty official hey ) I went in and added another disc of velour against the back making it 3 stacked total with the felt on the outside of the cup-side- side... side.
 
On the back of the baffle area  which was very restricted in size, I added a ring of felt then somehow managed to squeeze a ring of velour stuff.  Crammed it all back together and overtightened a screw heard a crack ( I gave it a hairline crack now , barely noticeable on the outside of the baffle ) . Too much stuff in it I guess.  it's barely there but no more entry. I may install black vinyl decal over the screw holes to remind myself.
 
He brought up the subject about damping ALL exposed interior surfaces, because we were mentioning that specifically and a few things pored over incessantly at that other thread. Lo and behold the dumba$$ that I am I had neglected to do the small area around the driver as in the previous picture.( it's inside the cup facing to the rear away from the head obviously )
 Seems to have made a difference all these last things.  Hasn't lost ANY clarity.
 
So is it a "thing" that the SFI's cannot put out a decent bass or?
These may be closer to neutral than heavy, but honestly  it's there but not extreme depth though and is very precise, doesn't drone on, seems fast. It's what i would have expected from an Electret or stat. Some may call this bass weak or "lite"
I did compare them to the Audio-Technica AT-705 Electret and the Stax SR-5 super fast A/B/C ( within 2-3 seconds ) and with this particular set-up  and EQ I have, the 705 is a lot of bass ( always been strong bass even on the old amps ),the Stax has a bit more, but from brief recollection it lingered compared to these Nakamichi's. I may be full of it but I'll put this out there anyhow. It's what  I think.
 
Hey unless you own all 3 of 'em and have this setup, don't judge ( Please... haha) Silence da hatuz... did I just say that.
 
Either that or the bass here is recessed/or neutral, and/or didn't hold as long. One thing though it's improved with this latest stuff even more.   Definitely closer to neutral . Clarity is awesome. It's just tight. I really dig this signature, although the low extreme bass is lacking. Using a standalone CD player's jack I just did a side by side with the HP-1's and no contest the HP-1's are bass monsters comparatively. Wonder if I should take that white felt off the back of the driver see what happens.
 
I'm gonna shut up now I am not much good at the descriptions. Usually go by the feel. This feels good.
 
 I may pick up a new amp this week, an older 2 channel Yamaha that has bypass on the filters, and when the tube amp gets recapped it will be the dedicated headphone amp so I can do attempt a better check on these.
 
Sorry for the long boring dry read.
 
Some extra thrilling pictures per Waulta's request.
Oh boy make a poster or t-shirt!
Has anyone made a coffee mug with their favorite ortho-related picture on it?
 
This is the interior side of the baffle. Driver rear is directly under that white felt disc.These rings are on top of the grey mass posted last page. One felt then one velour. No room for more. Better than what was there before: nothing but putty.

With polyfill spring-filler on top:

Somehow it all BARELY fit into this cup. Neoprene outer with bass vent ( hole-punch sized), craft felt, now  3 layers velour.
the slots in the felt edge ring need to be there to allow cable routing. Look closely and you can see some thin grey residue around the edge. This is the outer tapered ring that needs to mount all around in the baffle-side putty to create a full seal. 3 screw mounts can
be seen there. If you'll look to your right you will see the parliament buildings, constructed in 1867... The bus will stop for rest breaks every hour.

 Final product looks still the same:

 
This'll have to be it for tonight. Maybe remove felt off back of driver tomorrow and let the stuffing in the back try to tame the backwave.
Sounds good.
 
 
 
 

 
Quote:

Originally Posted by nick n /img/forum/go_quote.gif
 
So is it a "thing" that the SFI's cannot put out a decent bass or?

Click to expand...

 
A lotta folks sprain their "thing" trying to get bass from an SFI transplant. Not sure why, but there have been several plaintive cries. You, Nick the Pursuivant, have persevered.

so, who's grab those NAD RP18 ?
http://www.ebay.de/itm/NAD-RP-18-VINTAGE-HIGH-END-KOPFHORER-HEADPHONES-RP-18-/320768716758

its the Kapton one, actually...

They sure look nice and shiny almost like new!  A bit steep for price isn't it, or are they that rare?
Can't someone these days do up a classy looking quality build like that for mass consumption? Cmon.
 
I keep forgetting about that german site.

That has team Nico written all over it. 
 
And it's actually a decent price if my hazy euro conversion guesstimate is near target. 

Auction gone already? I didn't even get to look at the shiny pictures... 

Quote:

rhythmdevils said:

That has team Nico written all over it. 
 
And it's actually a decent price if my hazy euro conversion guesstimate is near target. 

Click to expand...

Nope, was none of us who sniped that Kapton. Our core team isn't that big, everyone who cares is equipped meanwhile...
 
 

Hey people. I came across some cheaper and what seems better product for deadening/damping. I wanted to post it in here rather than the t-50 thread. They can come here to find it
http://www.edesignaudio.com/index.php?cPath=1_24.
 
specifically the last 3 listed there:
 
[size=x-small]eDead v4 - TekLite [/size][size=x-small][size=xx-small]   [/size][/size][size=x-small]eDead 80[/size][size=x-small][size=xx-small]    [/size][/size][size=x-small]eDead 45 [/size][size=x-small][size=xx-small]              [/size][/size]sold per square foot. That's ridiculous prices. Go collect some bottles and you're set.
 
Going to order up some of it soon and have a stash.
 
[size=x-small][size=xx-small]@ $2                                   $2                $1      [/size][/size]
 
[size=x-small][size=xx-small]  [/size][/size]

Hey if it makes sense shipping wise to get a few more pieces sent up to Canada at the same time, I'll jump on the bandwagon.

Huh, a butyl based acoustic sealant... http://www.canadiantire.ca/AST/browse/3/HouseHome/1/HeatingAirConditioning/WeatherStripping/PRD~0641027P/Mono+Acoustical+Sealant.jsp?locale=en

 
Quote:

armaegis said:

Huh, a butyl based acoustic sealant... http://www.canadiantire.ca/AST/browse/3/HouseHome/1/HeatingAirConditioning/WeatherStripping/PRD~0641027P/Mono+Acoustical+Sealant.jsp?locale=en
 
>That could definitely fill up some awkward  spots, or even the entire back of the cup and get smoothed out .

Click to expand...

 
 
Well that above link I left for people seems very steep in shipping, at least to me in Canada, so in the course of digging around and running on instinct I managed to find this. With all the talk of Silverstone dampener, This looks a bit better. Apparently they developed it themselves, and patent details are available on request, as it says in the small print.
Nice  thing about this is that it's not simply a rebranded product, so you know at least who made it and what it is. And there's no unnecessary price hike for no reason.
 
Disclaimer:I have yet to buy some of this to try.No idea how it is.
 
Also for anyone who cares, there's big fancy colorful professional GRAPHS from testing.
Everybody in here likes the graphs, right.
 Check it out.  If you will notice from the various links, there are a few versions.

1.  Big Blocks for space filling ( not very applicable in headphones ) and some egg cratey type with larger surface area
2. 2 layer stuff various thicknesses
3. new 3 layer stuff in 3 thicknesses, 7, 12, 13 mm respectively. The 7 and 12 seem the most available.

        This 3 layer has the denser layer in the center decoupled from the mounting surface.
 
A really interesting read.
Here's the manufacturer:
http://www.acoustiproducts.com/en/acoustipack.asp
http://www.acoustiproducts.com/en/materials.asp  general overview a graph or two, and some details about its composition.
http://www.acoustiproducts.us/en/acoustipack-extra-s.asp  this is the single sheet . notice down at the bottom left there is sellers list for US/Canada
 
here's the North American Distributor, also a seller: See the nice graphs.
http://www.quietpcusa.com/AcoustiML-OEM-3-Layer-69-13mm-Soundproofing-Materials-P563C69.aspx  this is for the bulk OEM stuff large quantities.
 
Be aware there is both 2 and 3 layer stuff when looking, various thicknesses.
For instance the "EXTRA" single sheets come both in 12mm and 7mm.They are 18"by 17" I think.
I read a review that said this stuff has some heft to it.
 
 
Gonna try some soon ,hopefully, unless I miraculously come up with a stunning DIY Cheapo solution. Maybe someone's already tried it?
 
 
 
 
 

I've done this for grados but not closed cans... I've lined the inside of the cups with hot glue. Basically just placed a bead along the surface, then used the surface cone of the glue gone to spread it into a thin layer. To my ears it helps to smooth out the treble a bit.

Quote:

defectiveaudiocomponent said:

Listening impressions and more photos of the RT10
 
The extremely open design does result in somewhat weaker bass... but it has some rewards too. I put on Beethoven 9th, and the cavernous (note: in ortho terms) headstage that unfolded put a big grin on my face. The RT10 is somewhat mid-centric, but those are great sounding mids, like the usual PMB sound. Come to think of it, that experiment I did putting the drivers (without the headset) to my ears, that must have been the sound they aimed for with the RT-10. Since I got some deep bass then, it should be possible to get it when using the headset too. I might need to replace my broad pads with something narrower, so that my ears fit inside.
 
The headstage is very nice with other music as well, but with live music, it's something other vintage orthodynamics just don't do. The air damped driver, hanging freely surrounded only by foam, is what does the trick I guess. The wire mesh grille of the RT10 appears to be a somewhat better design than the broad bars of the PMB-80. The  DK830 appears to be a similar design, although without the cancellation vents, but it has that broad bar going across the middle of the grilles. It's also a good thing that they omitted the crappy volume control that they put on some other headphones.
 
All-in-all this might be the pinnacle of the PMB-style design. Until we hear impressions of yet another unheard ortho
It's a good and cheap introduction to the planar magnetic sound.


 

Click to expand...

What's your impression of the Magnat RT10 now, after a few months listening?

For damping considerations in custom cups, thought I'd post the insides of the Stax SR-50 I took apart the other day. Nothing fancy, just what appears to be loose cubes of rockwool (?) in an otherwise half-sphere cup.
 
Anyone know EXACTLY what the stuff is? I think it's some sort of wierd felty stuff. Someone chime in on this please. Long fiber wool?
 
Maybe this applies to orthos, maybe not, but it's utter simplicity is worth trying over all the crazy, but for the most part effective, schemes going on lately.
 
For those that don't know, these are the closed bass-heavy electrets that as far as I know use the same drivers as the 40 , maybe higher models too. But that's sort of irrelevant other than the fact that they are that much bassier due to being closed and this material.

As you can see not much to it.
 
 
 

Are there any good replacement pads for a Yamaha YH-3? I managed to pick these things up, but not surprisingly there's zero bass!
 
Are the Koss R10 pads decent?